Psychosis is an impaired perception of reality. It may be caused by a psychiatric disorder (primary psychosis) or it may be the result of substance use, an underlying medical condition, or a mood disorder (secondary psychosis). Acute psychosis is a psychiatric emergency. The management of acute psychosis includes ensuring patient and staff safety, reducing patient agitation, ruling out a medical cause for the thought disturbance, and facilitating the appropriate disposition. Patient agitation may need to be managed before an assessment can be completed; nonpharmacological methods should be attempted first, but rapid escalation to pharmacotherapy may be necessary. Diagnostic testing is guided by the patient's history and clinical presentation. The use of broad, nondirected panels of tests is discouraged. Treatment depends on the underlying cause, but most patients require admission and psychiatry consultation.
- Psychosis: an impaired perception of reality evidenced by one or more of the following thought disturbances 
- Primary psychosis: psychosis resulting primarily from a psychiatric disorder, e.g., schizophrenia 
- Secondary psychosis: psychosis resulting primarily from a general medical condition and/or the effect of a substance 
- Psychotic disorder: a disease or condition that produces psychosis
Causes of primary psychosis
Schizophrenia spectrum disorders
|Schizophrenia spectrum and other psychotic disorders |
|Duration of symptoms||Clinical features||Social and occupational functioning|
|Schizophrenia|| || || |
|Schizophreniform disorder|| |
|Brief psychotic disorder|| |
|Schizoaffective disorder|| || |
|Delusional disorder|| || |
|Other psychotic disorder: delusional symptoms in the partner of an individual with a delusional disorder|| || |
- Mood disorder with psychotic features
- Anxiety disorders with psychotic features: e.g., 
- Schizotypal personality disorder
- Others: Psychotic features can occur in patients with the following personality disorders but are not characteristic.
Causes of secondary psychosis 
Psychotic disorder due to another medical condition
- Multifactorial disorders: : e.g., delirium
- Autoimmune disorders: , e.g., systemic lupus erythematosus, anti-NMDA receptor encephalitis
- Endocrine disorders: , e.g., hyperthyroidism or thyrotoxicosis, hypercortisolism, Wilson disease
- Metabolic disorders: , e.g., porphyria, vitamin B12 deficiency
- Neurological illness: , e.g., dementia, traumatic brain injury, neoplasm (brain tumors), encephalitis, seizure disorders (e.g., temporal lobe epilepsy)
Substance-induced psychotic disorder
- Recreational substances with psychoactive effects
Medications with adverse psychoactive effects
- Analgesics (e.g., opioids)
- Sedatives or hypnotics
- Muscle relaxants (e.g., cyclobenzaprine)
- Antihistamines (e.g., diphenhydramine)
- Antidepressants (e.g., SSRIs)
- Cardiovascular medications (e.g., clonidine)
- Antihypertensive medications (e.g., methyldopa)
- Anticonvulsants (e.g., levetiracetam)
- Antiparkinson medications (e.g., dopaminergics)
- Chemotherapy agents (e.g., bleomycin)
- Hallucinations: perceptual abnormalities in which sensory experiences occur in the absence of external stimuli
- Illusions: a perceptual abnormality in which real external stimuli are misinterpreted
- Auditory (most common)
- Somatic (tactile)
- Definition: fixed, false beliefs that are maintained despite being contradicted by reality or rational arguments and that are not related to one's religious beliefs or culture
- Bizarre delusions: delusions that cannot be true or are inconsistent with the patient's social and cultural norms (e.g., a patient insisting that they can fly)
- Nonbizarre delusions: delusions that can be true or are consistent with the patient's social and cultural norms (e.g., a patient insisting that they have won the lottery when this is not the case)
- Grandiosity: The patient insists that they have special powers or importance.
- Ideas of reference: The patient believes that normal events are of special importance to them (e.g., an individual might feel that a television reporter is talking about them).
- Paranoia: The patient has an exaggerated distrust of others and is suspicious of their motives.
- Persecutory: The patient insists that they are being cheated on, conspired against, or harassed.
- Erotomania: The patient believes that other individuals are in love with them.
- Jealousy: The patient believes their partner is unfaithful without justification.
- Somatic delusion: The patient believes they are experiencing a bodily function or sensation when there is none present.
- Mixed delusions: two or more delusions occurring simultaneously; no delusion is predominant over the other.
- Unspecified delusions: a delusion that does not fit the criteria of other types or that cannot be clearly defined
Disorganized thought and disorganized speech processes
Disorganized thought refers to a disturbance in the logical connection between thoughts or the flow of thoughts. Disorganized speech is a collection of speech abnormalities that lead to incoherent speech.
- Loose associations: incoherent thinking expressed as illogical, sudden, and frequent changes of topic
- Word salad: incoherent thinking expressed as a sequence of words without a logical connection
- Tangential speech: nonlinear thought expressed as a gradual deviation from a focused idea or question
- Neologisms: the creation of new words with idiosyncratic meanings
- Echolalia: involuntary repetition of another's words or sentences
- Flight of ideas: quick succession of thoughts usually demonstrated in a continuous flow of rapid speech and abrupt changes in topic
- Clang association: use of words based on rhyme patterns rather than meaning
- Circumstantial speech: nonlinear thought expressed as a long-winded manner of explanation, with multiple deviations from the central topic, before finally expressing the central idea
- Thought-blocking: an objective observation of an abrupt ending in a thought process, expressed as a sudden interruption in speech
- Pressured speech: accelerated thoughts that are expressed as rapid, loud, and voluminous speech, often in the absence of social stimulation
Associated clinical features
- Primary psychotic disorders: e.g., negative symptoms of schizophrenia, catatonia, cognitive impairment
- Other psychiatric conditions: E.g., see “Mood disorders,” “Anxiety disorders,” and “Substance use disorders.”
- Underlying medical conditions: e.g., focal neurological deficits
Schizophrenia typically manifests with a prodrome of negative symptoms and psychosis (e.g., social withdrawal) that precedes the positive psychotic symptoms (e.g., hallucinations and bizarre delusions).
A medical assessment is performed in all patients with acute psychosis to differentiate between primary and secondary psychosis and to identify comorbidities that may require medical treatment. 
Initial management 
Stabilization: Manage acute agitation if present (see “Approach to the agitated or violent patient” for details).
- Begin with .
- Consider prescribing .
- Identify and treat .
- Include the following as part of a thorough
from the patient (or collateral history from friends/family members/care providers) :
- Previous diagnosis of psychosis
- Prodromal symptoms (e.g., depression, thought disturbance)
- Time course of symptom onset (e.g., abrupt onset)
- History of head trauma or new neurological symptoms (e.g., headache)
- Medication and drug history
- Other medical history (e.g., thyroid disease, autoimmune disease, porphyria, Cushing syndrome)
- Recent life stressors
- Family history of neurological or psychiatric disorders
- Include the following in the physical examination: 
- Include the following as part of a thorough
- Differentiate through clinical evaluation.
- Perform physical examination. as guided by history and
If there is a language or cultural barrier, use a trained interpreter with an awareness of the patient's cultural beliefs. 
The medical evaluation should indicate whether the patient is medically stable, include recommendations for further medical care if needed, and address whether treatment in a psychiatric facility is medically appropriate. Use of the term “medical clearance” is discouraged. 
- Hospitalize any patient with psychosis who is a danger to themselves or others: See “ ” and “ .”
- Consult psychiatry for all patients being considered for outpatient treatment.
- Treatment in an outpatient psychiatric facility may be appropriate if:
- The patient is not a danger to themselves or others.
- The patient is able to attend the outpatient facility regularly.
- A receiving facility has been identified and agrees to accept the patient.
Indications for diagnostic testing 
- First episode of psychosis
- Suspected secondary psychosis 
- Admission to a psychiatric facility that cannot perform diagnostic testing
- Testing as a courtesy for a receiving psychiatric facility with limited resources may be performed but should not delay the patient transfer. 
A thorough history, physical examination (including vital signs), and cognitive assessment are required for the medical evaluation of patients with psychosis. Further diagnostic studies are not routinely required but may be warranted if secondary psychosis is suspected. 
Differentiating primary from secondary psychosis
|Clinical indicators for primary and secondary psychosis |
|Indicator||Primary psychosis||Secondary psychosis|
|Age|| || |
|Speed of onset|| || |
|Physical examination|| |
|Mental status examination|| |
|Hallucinations|| || |
|Drugs|| || |
Diagnostic studies for secondary psychosis 
- Laboratory studies
- Imaging 
- Other studies
Management of agitation
For more detailed information, see “.”
- Urgently identify and treat .
- Attempt nonpharmacological if appropriate.
- Ensure patient and staff safety; identify .
- Prescribe if indicated (e.g., the patient's behavior poses a danger to themself and/or others). 
- Consider if violent behavior is refractory to and .
- Continue assessment and treatment of the psychosis once agitation has resolved.
|Pharmacotherapy for managing agitation in acute psychosis |
|Type of psychosis||Recommended regimens|
Monitoring for adverse reactions to antipsychotics
- Extrapyramidal symptoms, particularly acute dystonia, may accompany the acute administration of antipsychotics. 
- Second-generation antipsychotics have a lower risk for extrapyramidal symptoms than first-generation antipsychotics. 
- To reduce the incidence of extrapyramidal symptoms, consider coadministration of an anticholinergic (e.g., benztropine) or an antihistamine (e.g., diphenhydramine) with the antipsychotic medication. 
- See “. ” for more information on treatment, including dosages
Cardiac arrhythmias 
- Antipsychotics have the potential to increase the QT interval.
- Patients with , particularly those with a QTc interval > 500 ms, are at risk for dysrhythmias, e.g., . 
- If a patient has an increased baseline QTc interval , choose an antipsychotic with a lower risk of QT prolongation. 
- Repeat an ECG after the drug level reaches a steady state; if the QTc interval is now > 450 ms in men or > 460 ms in women, or has increased by > 60 ms, consider an alternative pharmacological agent. 
- : a rare but life-threatening complication of antipsychotics 
- Refer to psychiatry for:
- See also “Schizophrenia," “Major depressive disorder,” “Bipolar disorder,” and “Anxiety disorders.”
- Secondary psychosis
Acute management checklist for psychosis
- Rule out life-threatening causes of an acutely altered mental state (see “Critical causes of AMS”).
- Treat agitation as required to ensure patient and staff safety and facilitate patient assessment.
- Obtain a full history and physical examination.
- If secondary psychosis is suspected, perform diagnostic studies.
- Refer to psychiatry if primary psychosis is suspected.
- Treat underlying conditions if secondary psychosis is suspected.